Scala: Exposing a JDBC ResultSet through a generator (iterable) -

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i've got set of rows in database, , i'd provide interface spin through them this:

def findall: iterable[myobject]

where don't require having instances in memory @ once. in c# can create generators using yield, compiler takes care of converting code loops through recordset iterator (sort of inverting it).

my current code looks this:

def findall: list[myobject] = {   val rs = getrs   val values = new listbuffer[myobject]   while ( rs.next() )      values += new valuefromresultset(rs)   values.tolist }

is there way convert not store entire set in memory? perhaps use comprehension?

try extending iterator instead. haven't tested it, this:

def findall: iterator[myobject] = new iterator[myobject] {   val rs = getrs   override def hasnext = rs.hasnext   override def next = new valuefromresultset(rs.next) }

this should store rs when it's called, , otherwise light wrapper calls rs.

if want save values traverse, check out stream.


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